The environmental movement has not always been known for its coordination. But one effort to orchestrate the many interests and brands out there in green advocacy is the Partnership Project, a coalition of the 20 largest such groups in the country. The effort has some friends with deep pockets.

Started in 1999, the Partnership Project is an initiative to pool the influence, membership base, and strategy of the top environmental advocacy groups in the country. There are 20 members, each with a seat on a board of directors, and 10 representatives in an executive committee. Members are all environment-focused, and many belong to grassroots groups, but they vary quite widely. You’ve got the legal firm Earthjustice, rabble rousers Greenpeace, free-market greens at EDF, and geeks from the Union of Concerned Scientists.

But the diversity of interests is precisely why the arrangement came about. There are many players out in the field and in meeting rooms, so rather than stepping on each others’ toes all the time, they formed the club.

The name is so innocuous and the individual members so high-profile that the whole thing might sound a bit shadowy, but it’s mostly a way to pool shared efforts and avoid conflicts on the big issues, while leaving the separate brands and strategies intact. For example, they are currently making a big push to defend the Obama EPA’s coal power plant rules.

The Partnership Project is, however, an incorporated nonprofit, and serves as a channel for funding. Foundations adore this kind of endeavor because they often consider themselves facilitators first, and love to organize a good coalition. (Note there is also a 501(c)(4) Partnership Project Action Fund set up for lobbying purposes, but funding is not included here.)

Here are the Partnership Project’s biggest fans:

Sea Change: This is the PP’s biggest backer. The philanthropy of Nathaniel Simons, Sea Change is pouring money into the climate change fight. Simons is a hedge fund manager, and son of Jim Simons, also a hedge fund manager and founder of science research funder The Simons Foundation. Sea Change is not a big believer in transparency, with almost no public presence despite its tremendous funding. It’s given more than $15 million since 2008 to the Partnership Project alone.

Hewlett Foundation: We just wrote about their most recent funding for this coalition, but this huge energy funder stepped up giving in the past few years to as much as $3.5 million in one grant. The latest grant supports the coalition’s work to defend historic proposed EPA limits on coal plant emissions.

Turner Foundation, Inc.: Ted Turner’s foundation is known mostly for conservation and wildlife protection, and the Partnership Project has mostly been devoting itself to energy and climate lately. But Turner has still given regular grants since 2003 in the low six figures, although one early grant was for over a million.

From there, the list drops off a bit. Packard gave $750,000 back in 2003, but hasn’t funded the effort since. Surdna has given a couple of six-figure grants, as has John Merck Fund. And believe it or not, even the Walton Family Foundation got in on the party with a grant of $125,000 in 2010.

Read more about the Partnership Project, including a full list of members, here.